Aircraft may encounter expected threats along a route during the transit portion of a mission. Such threats may include weather, winds, terrain, obstacles, a hostile surface threat, and a hostile airborne threat. These expected or pre-planned threats may pose a certain level of risk to an aircrew and passengers before a mission is begun. A commander or dispatcher may rely on these known threats to make critical decisions concerning the flight.
Such critical pre-mission decisions may include a fueling amount, a cargo load, a weapons loadout, a specific configuration (e.g., one or two external fuel tanks, more or less ordnance, more counter air ordinance, more counter surface ordnance), a dispatch limit based on external statutory regulations, and aircrew flight time limitations. As a flight may progress over time, these pre-mission decisions may become inaccurate or obsolete.
Aircraft may also encounter unexpected threats en-route to a destination. Such unexpected threats may include a changed weather system, a pop-up signal jammer, an unplanned surface-to-air missile radar or battery, a volcano eruption, or a recently erected obstacle. Since risk-free paths may be ineffective for a number of reasons, these unexpected threats may require a pilot to shoulder an unknown additional level of risk in order to accomplish the primary objectives of the mission.
Unexpected threats may pose additional risk to an aircrew if the aircrew makes a routing decision based on inaccurate or obsolete information. Also, the aircrew may suffer loss of situational awareness leading to a routing decision which may lead the aircraft into a more hazardous situation than would be the case had an accurate routing decision been made or the aircraft has stayed the originally planned route.
A specific route of flight may present a specific level of risk to a pilot. For example, to reach a target at a required time-on-target (RToT), the flight path may be required to penetrate known threat zones of low level lethality. Such low level lethality zones may include a detection range of a surveillance radar system or within a detection range of a target tracking radar system.
These low level lethality threat zones however do not include zones within which a flight may experience a high level of lethality. Such high level lethality may be found within the engagement range of surface to air missiles or within the range of air to air weapons. The lethality of these high lethality threat zones may be reduced however with a short exposure in such a threat zone.
Pilots are under considerable stress in a combat environment. Decisions made based on erroneous information or decisions made quickly without regard to possible threats may place an aircraft in a more lethal zone than a previous zone. Should a decision be inaccurate, consequences may be catastrophic.
Traditional methods of risk reduction may be labeled differently by entities tasked with least risk routing. The U.S. Air Force labels the technique used by some Air Force planners Reduced Risk Routing as the goal may be to reduce risk inherent to a specific routing. The intended purpose of the Reduced Risk Routing capability may be to facilitate a pilot's decision making process, while increasing aircraft survivability in dense threat environments.
Commercial air carriers may label a specific route as a “track” offering a preferred routing in a geographic area. For example, North Atlantic Tracks are published daily and indicate to aircraft transiting the North Atlantic a preferred route through that airspace based on winds, weather, and additional factors.
Sea surface traffic may also endeavor to transit on routes which offer the least amount of risk for ships at sea. For example, a Sail on Routes that Reduce Risk guidance may be offered to navigators to enable ships to transit an area while doing so at a lower risk level.
A ground based platoon commander may visually survey a geographical area before determining a level of risk associated with the proposed routing. Should the commander visually acquire a threat along the route, he may alter the proposed routing to reduce or eliminate the threat.
On-board computing resources may be limited to reduce weight and power consumption. For example, computing resources on a fighter jet may be a fraction of that available to a team of route planners in a ground based operations center. Placing powerful heavyweight computers onboard an aircraft may be one traditional method of solving the problem, however, aircraft performance would suffer greatly as an equal reduction in payload must be made.
However, each of these attempts at real time path planning has proven unreliable or ineffective when attempted to be incorporated in a lightweight tactical platform.
Consequently, a need exists for development of a real time risk-aware contingency flight re-planner capable of automated presentation of accurate, time sensitive, re-route planning information on-board a light weight platform. Each re-route including a threat level associated with the re-route enabling a decision maker to make an informed threat-based decision.